1 // SPDX-License-Identifier: GPL-2.0-only
5  * Driver for Texas Instruments' ADC084S021 ADC chip.
29 	/* Buffer used to align data */
31 		__be16 channels[4];  member
39 	__be16 rx_buf[5]; /* First 16-bits are trash */
68  * adc084s021_adc_conversion() - Read an ADC channel and return its value.
70  * @adc: The ADC SPI data.
73 static int adc084s021_adc_conversion(struct adc084s021 *adc, __be16 *data)  in adc084s021_adc_conversion()  argument
75 	int n_words = (adc->spi_trans.len >> 1) - 1; /* Discard first word */  in adc084s021_adc_conversion()
79 	ret = spi_sync(adc->spi, &adc->message);  in adc084s021_adc_conversion()
84 		*(data + i) = adc->rx_buf[i + 1];  in adc084s021_adc_conversion()
93 	struct adc084s021 *adc = iio_priv(indio_dev);  in adc084s021_read_raw()  local
103 		ret = regulator_enable(adc->reg);  in adc084s021_read_raw()
109 		adc->tx_buf[0] = channel->channel << 3;  in adc084s021_read_raw()
110 		ret = adc084s021_adc_conversion(adc, &be_val);  in adc084s021_read_raw()
112 		regulator_disable(adc->reg);  in adc084s021_read_raw()
117 		*val = (*val >> channel->scan_type.shift) & 0xff;  in adc084s021_read_raw()
121 		ret = regulator_enable(adc->reg);  in adc084s021_read_raw()
125 		ret = regulator_get_voltage(adc->reg);  in adc084s021_read_raw()
126 		regulator_disable(adc->reg);  in adc084s021_read_raw()
134 		return -EINVAL;  in adc084s021_read_raw()
139  * adc084s021_buffer_trigger_handler() - Read ADC channels and push to buffer.
141  * @irq: The interrupt number (not used).
147 	struct iio_dev *indio_dev = pf->indio_dev;  in adc084s021_buffer_trigger_handler()
148 	struct adc084s021 *adc = iio_priv(indio_dev);  in adc084s021_buffer_trigger_handler()  local
150 	mutex_lock(&adc->lock);  in adc084s021_buffer_trigger_handler()
152 	if (adc084s021_adc_conversion(adc, adc->scan.channels) < 0)  in adc084s021_buffer_trigger_handler()
153 		dev_err(&adc->spi->dev, "Failed to read data\n");  in adc084s021_buffer_trigger_handler()
155 	iio_push_to_buffers_with_timestamp(indio_dev, &adc->scan,  in adc084s021_buffer_trigger_handler()
157 	mutex_unlock(&adc->lock);  in adc084s021_buffer_trigger_handler()
158 	iio_trigger_notify_done(indio_dev->trig);  in adc084s021_buffer_trigger_handler()
165 	struct adc084s021 *adc = iio_priv(indio_dev);  in adc084s021_buffer_preenable()  local
169 	for_each_set_bit(scan_index, indio_dev->active_scan_mask,  in adc084s021_buffer_preenable()
170 			 indio_dev->masklength) {  in adc084s021_buffer_preenable()
172 			&indio_dev->channels[scan_index];  in adc084s021_buffer_preenable()
173 		adc->tx_buf[i++] = channel->channel << 3;  in adc084s021_buffer_preenable()
175 	adc->spi_trans.len = 2 + (i * sizeof(__be16)); /* Trash + channels */  in adc084s021_buffer_preenable()
177 	return regulator_enable(adc->reg);  in adc084s021_buffer_preenable()
182 	struct adc084s021 *adc = iio_priv(indio_dev);  in adc084s021_buffer_postdisable()  local
184 	adc->spi_trans.len = 4; /* Trash + single channel */  in adc084s021_buffer_postdisable()
186 	return regulator_disable(adc->reg);  in adc084s021_buffer_postdisable()
201 	struct adc084s021 *adc;  in adc084s021_probe()  local
204 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc));  in adc084s021_probe()
206 		dev_err(&spi->dev, "Failed to allocate IIO device\n");  in adc084s021_probe()
207 		return -ENOMEM;  in adc084s021_probe()
210 	adc = iio_priv(indio_dev);  in adc084s021_probe()
211 	adc->spi = spi;  in adc084s021_probe()
214 	indio_dev->name = spi_get_device_id(spi)->name;  in adc084s021_probe()
215 	indio_dev->modes = INDIO_DIRECT_MODE;  in adc084s021_probe()
216 	indio_dev->info = &adc084s021_info;  in adc084s021_probe()
217 	indio_dev->channels = adc084s021_channels;  in adc084s021_probe()
218 	indio_dev->num_channels = ARRAY_SIZE(adc084s021_channels);  in adc084s021_probe()
221 	adc->spi_trans.tx_buf = adc->tx_buf;  in adc084s021_probe()
222 	adc->spi_trans.rx_buf = adc->rx_buf;  in adc084s021_probe()
223 	adc->spi_trans.len = 4; /* Trash + single channel */  in adc084s021_probe()
224 	spi_message_init_with_transfers(&adc->message, &adc->spi_trans, 1);  in adc084s021_probe()
226 	adc->reg = devm_regulator_get(&spi->dev, "vref");  in adc084s021_probe()
227 	if (IS_ERR(adc->reg))  in adc084s021_probe()
228 		return PTR_ERR(adc->reg);  in adc084s021_probe()
230 	mutex_init(&adc->lock);  in adc084s021_probe()
233 	ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, NULL,  in adc084s021_probe()
237 		dev_err(&spi->dev, "Failed to setup triggered buffer\n");  in adc084s021_probe()
241 	return devm_iio_device_register(&spi->dev, indio_dev);  in adc084s021_probe()